According to Ian Dury’s 1970s funk single, sex, drugs and rock 'n' roll are all "very good indeed". His belief comes from how the three activities activate the brain's reward circuit – a neural pathway dictated by the chemical dopamine; the higher the level of dopamine, the greater the feelings of pleasure. To control this system, the brain also employs other circuits that in their default state prevent dopamine release. Interconnectivity of the dopamine system (in green) and the inhibition network (in red) is evident when viewed together (centre) within this reward circuit’s command centre. But drugs such as heroin, disable this brake, thus allowing dopamine to flood the system. This chemical influx, as with all drugs, is far quicker and stronger than natural rewards, leading to a hedonistic high that eclipses all natural rewards. So, while sex and rock 'n' roll may be very good, for an addict drugs are even better.
Written by Jan Piotrowski
BPoD is also available in Catalan at www.bpod.cat with translations by the University of Valencia.